Abstract:
A variable valve lift system may include a roller finger follower having an end connected with a valve and a roller mounted thereto. A hydraulic lash adjuster supports another end of the roller finger follower and has operating modes which are changed to a high lift mode or a low lift mode according to supplied hydraulic pressure to change a height of the hydraulic lash adjuster. A hydraulic pressure supplying portion supplies the hydraulic pressure to the hydraulic lash adjuster. A cam is mounted to a camshaft and contacts the roller of the roller finger follower. The cam has a first ramp and a second ramp formed thereon.
Abstract:
A linear variable differential transformer (LVDT) for monitoring engine valve position is disclosed. The system includes a valve guide having an elongated recess through it. The engine valve has a valve head and a valve stem with two adjacent materials having different magnetic properties meeting at an interface. The valve stem fits and moves linearly within the valve guide, and the valve head closes an engine combustion chamber. It also includes monitoring coils within the valve guide that create a signal related to the position of the interface within the valve guide. An engine control unit (ECU) is coupled to the monitoring coils and receives and analyzes the signal from the monitoring coils to determine operation of the valve.
Abstract:
An internal combustion engine includes a plurality of cylinders, intake valves (31) provided respectively in the cylinders, and a variable valve mechanism (600) for changing a valve characteristic of the intake valves (31). A motor (210) drives the variable valve mechanism (600). A motor controller (150) controls the motor (210). The internal combustion engine can be operated in a cylinder deactivation mode for retaining the intake valves (31) of some of the cylinders in a valve closing state. When the internal combustion engine returns from the cylinder deactivation mode, the motor controller (150) executes overlap adjustment processing for controlling the valve characteristic such that valve opening periods of the intake valves (31) are not overlapped between the cylinders.
Abstract:
A durable system for controlling variable valve actuation of an engine valve corresponding to a cylinder of an automobile engine. The system includes first and second crowned cams having first and second lift profiles and a rocker arm assembly. The rocker assembly includes a first arm having an end connected to said engine valve, having a high impact roller following the first crowned cam operating the engine valves according to a first lift profile. The rocker arm assembly also includes a second arm having durable slider pads riding on the second crowned cam to operate said engine valve according to a second lift profile. A latch secures the second arm relative to the first arm when in a latched position causing the valve to operate according to a second lift profile. The valve operates according to a first lift profile when the latch is not in the latched position.
Abstract:
A variable valve actuating mechanism comprising a camshaft having two concentric cam lobes that may be rotated relative to one another a summation lever engaging with both cam lobes, a valve actuating rocker pivotally connected to the summation lever and engaging with a hydraulic lash adjuster at a first end and with a valve at a second end, and a shim surface movable with the pivot axis connecting the summation lever to the valve actuating rocker for limiting the expansion of the hydraulic lash adjuster to control clearance in the rocker system, wherein, in order to reduce friction, the shim surface abuts with a stationary stop surface that forms part of a camshaft support bearing.
Abstract:
A system for controlling variable valve actuation in an automobile engine. A first cam has a first lift profile and a second cam has a second lift profile. A rocker arm assembly engages the cams having a first arm for riding on the first cam, and a second arm for riding on the second cam. The second arm has an activatable latch capable of securing the second arm to the first arm when latched. When the first arm is secured to the second arm, the rocker arm assembly achieves a first lift profile and when the first arm is not secured to the second arm, the rocker arm assembly achieves a second lift profile. A non-contact sensor mounted adjacent the rocker arm assembly is adapted to monitor and create data indicative of whether the first arm is secured to the second arm.
Abstract:
A lash adjuster includes a plunger and a partitioning member inserted into the plunger. The plunger has a bottom wall with a valve hole and a peripheral wall having an oil passage hole. The plunger defines a high-pressure chamber between the bottom wall and a body. The partitioning member has a baffle having first and second plate surfaces. The baffle has an upper end serving as oil passage end. The plunger has an interior divided into two spaces. The passage hole is located at one space side. An oil passage is defined by an inner peripheral wall surface of the plunger and the first plate surface. A low-pressure chamber is defined at the other space side to store hydraulic fluid. The low-pressure chamber supplies the fluid through the valve hole into the high-pressure chamber and is defined by the inner peripheral wall surface of the plunger and the second plate surface.
Abstract:
A switching roller finger follower including: a housing including first and second walls; a first secondary arm pivotably connected to the housing and including a first groove; a second secondary arm pivotably connected to the housing and including a second groove; and a roller disposed between the first and second walls and including an axle passing through the walls and having a first end disposed in the first groove and a second end disposed in the second groove. A method of fabricating a switching roller finger follower, including: disposing a roller between first and second walls for a housing; passing an axle through the roller and the walls; pivotably connecting first and second secondary arms to the housing; disposing a first end of the axle in a first groove in the first arm; and disposing a second end of the axle in a second groove in the second arm.
Abstract:
A system for diagnosing malfunctions in a variable valve actuation device is disclosed. The system has a rocker arm assembly that includes: a first arm, a second arm with the first and second arms attached at a first end, a hydraulically operated latch assembly that functions to secure the first arm to the second arm when latched. The rocker arm assembly pivots upon a hydraulic lash adjuster. It also includes a source of pressurized fluid connected to a hydraulic valve that provided fluid high or low pressure fluid to the hydraulically-operated latch. The latch may be operated by a remote device. A pressure transducer is positioned within the hydraulic lash adjuster (HLA) and is adapted to create a signal indicating the fluid pressure in the HLA. A control unit is coupled to the hydraulic valve and the pressure transducer, and is adapted to sense engine operation parameters, actuate the hydraulic valve, read the signal from the pressure transducer and identify malfunctions of the rocker arm assembly based upon the signal from the transducer.
Abstract:
A system for controlling variable valve actuation in an automobile engine is disclosed. A first cam has a first lift profile and a second cam has a second lift profile, both profiles having a base circle portion and a lift portion. A rocker arm assembly engages the cams having a first arm for riding on the first cam, and a second arm for riding on the second cam. The second arm has an activatable latch capable of securing the second arm to the first arm when latched. The latch may only be latched while the arms are riding on the base circle portion of the cams. When the first arm is secured to the second arm, the rocker arm assembly achieves a first lift profile and when the first arm is not secured to the second arm, the rocker arm assembly achieves a second lift profile. A non-contact sensor mounted adjacent the rocker arm assembly is adapted to monitor and create data indicative of whether the first arm is secured to the second arm. An engine control unit (ECU) for controlling functioning of at least one aspect of said engine operation receives the signal from the non-contact sensor and control functioning of the at least one aspect of said engine operation based upon the received signal from the non-contact sensor.